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Dino A
iOS Development Techdegree Student 786 PointsPassing on the variable
At around 6:14 Amit talks about passing on a variable to a double. Is there more than one way to write the code for that? For e.g. This is how it is in this lesson:
let areaInMeters = Double(area) / 10.764
Could you also write it like this:
let areaInMeters: Double = area / 10.764
much appreciated
2 Answers
Justin Black
24,793 PointsIn short, no. It would still fail.
Reason being we are taking the area, which will always equal a whole number and as such is of Int type. In order to divide that by 10.764, we have to convert that to a double by typecasting the variable to be one.
Otherwise, you get the error: 'Int' is not convertible to 'Decimal'
Dino A
iOS Development Techdegree Student 786 Pointsgotcha. Now I get it. Thanks for taking the time to help.
Dino A
iOS Development Techdegree Student 786 PointsDino A
iOS Development Techdegree Student 786 PointsI appreciate the reply Justin. I understand what you are saying. I just don't get why in the numbers "Numbers" course section you would write the code like this:
var version: Double = 1.0
But in "Binary operators" its written like this:
let areaInMeters = Double(area) / 10.764
Why isn't there a colin after areaInMeters like there is in the code above that? And why does area have to be in brackets? I guess what I am really asking is what is the difference the way both of those lines are written?
I hope this was clear. Its probably the simplest answer but its not computing.
cheers
Justin Black
24,793 PointsJustin Black
24,793 PointsThe first way would be called a 'type set' or typesetting. This is because you are explicitly telling the application that the variable must contain a double.
The 2nd is type-casting. You are taking the value of one type, and converting it to another. I imagine he did this more so as a reference to type-casting, without really explaining it well.
You could do it the way you suggest, but you'd have to do it for the height, width and area.